Many years ago I helped a friend find S9+ noise on 6 meters. I used HT to track it down to neighbors home a couple blocks away. They were very nice and let us in their house and it turned out to be the power supply on an electric blanket. The neighbors unplugged it and noise was gone and when I looked it up that device had a recall for possible fire hazard so the home owners were happy we talked with them. The next day another S9 noise came and we tracked that to a friends shop when it was closed on weekend. Turned out it was caused by cordless phone base that had built in answering machine. It only made the noise if someone left a message in it . Our friend was also a ham and he said that the answering machine part of that got turned on that weekend by accident and he normally never used it.
A friend of mine had to rewire his whole solar roof (warranty, but a öotnof work) and replace electronics on it, because the neighbouring amateur radio station detected interférence from it. Before they detected even interferences from the train (BLS). Both of them had to fix it, as BAKOM told them so.
I did a similar exercise at two similar tower block homes in UK and in Germany. The noise levels in UK were 30 dB higher than in Germany leading me to believe that there may be different regulations about sources of noise in the two countries. In UK I have a chinese LiFePO4 battery charger which totally wipes out all HF bands. It is by far the worst polluter. Also in the block I imagine someone is still using a CRT TV as the harmonics seem to change with scene changes in a video signal !
I bought a LiFePo charger for our remote station as a backup for solar. It is a huge polluter, too. Unfortunately, you do not see it before you buy :-(
great video. as a swede, i can tell that each solar installation needs to approve CE, therefore, as a owner of example multiple inverters, sush as microinverters, the CE stamps needs to be revalid as the hole installation is complete. (the install of microinverters does not say the CE stands for multiple installed microinverters, only that it will work with multiple. So in other words, the CE only comply with one unit and not the whole solar installation.. ) //73
@@HB9BLA oh man.. that sucks... here they need to comply to CE and with that, EUs EMC directive..so without review the installation, they cant just say "it comply".. // 73
I live in Houston TX USA where interference is almost continuous from 400khz to 30mhz. It is a "white noise" looking signal that seems to come from all directions. The amplitude is huge, on the order of 5 microvolts per meter so any serious short wave or other long distance operation is futile.
What I did: took out all the fuses in my flat and put them back in one after the other. That's how I found the room that was causing the problem. Then took all the plugs out and put them back in again. So I found the external hard drive that was causing the S9 noise. vy73 de Micha, DD0UL
Thanks for your video! Can you recommend a cheap/affordable shortwave radio to detect emissions within the home please? The models in your video look to cost around the £200 mark which seems a bit pricey for me, but I am not familiar with how much they should cost and what functionalities are required. Thank you!
Nice video. My experience is.... cheap (Chinese) often causes troubles. More expensive... even from China makes in many cases the difference. At home I have a (very cheap) gas powered generator. I can assure it, if I turn on over here, you'll probably will detect the interference in your shack ;-) ! Of course, I never use it, I got it for free for testing.
I am not sure if the price can be used as an indicator. I have unexpensive quiet powerbanks and a quite expensive but "loud" LiFePo charger. It seems to be a bit of luck. And I have buck and boost converters from one supplier that are quiet (the exact same looking one from another supplier was "loud". So I stick with this supplier and it looks OK up till now.
this is why some circuits from 70' or 80' don't work very well in today's "noisy" homes :( It is annoying because it reduces drastically the range of some DIY built devices :(
Your video comes at a very good time! My pal and I are trying to discover why his Sonoff S31's running Tasmota keep dropping off his network. These are 2.4Ghz WiFi. I have the same devices on my network and do not have this problem. He is in a completely different urban area, the Highland Park area of St Paul, MN. I live in suburban Burnsville, MN some 25 miles or so from his location. He has other 2.4Ghz devices that are not affected. I am suspecting radio interference as a potential cause. Besides following the general process you describe, do you have any suggestions about finding interference on the 2.4Ghz WiFi band? We have SDR USB dongles. Many thanks!
Common SDR dongle receivers (RTL2832U) cannot sample the 2.4GHz Wifi band. SDR-Play, HackRF etc are more expensive, but can go up to 6GHz. Good luck finding the issue.
The 2.4GHz band is quite used in many locations. So it easily can be that this device has issues with crowded channels and the source is not QRM but other 2.4GHz devices. As mentioned by @squelchstuff, These dongles do not work up to 2.4GHz. But maybe you can chart a rough coverage of the channels using a Smartphone map? ( Google "ESP32 / 8266 WiFi Signal Strength" ) because CZcams does not allow links anymore.
As Andreas says, you might have more luck with some of the survey apps available for mobile and desktop. They'll show which channels are in use in the locality, signal strength etc. It may simply be a case of manually selecting a less congested channelled, as many users leave their APs on the default channel 1. Search wifi mapper or similar. Netstumbler used to be a popular choice, and many are based on that. As an aside, it seems that some ESP based IOT devices can be prone to this behaviour as is often reported. I've noticed some households with smart lights flashing on and off that have obviously lost their pairing, and have defaulted to setup mode while the residents are away. Burglars must be having a field day. Not smart...
There has been a specific 2.4 GHz spectrum analyzer USB dongle for the last 20 years for about $200 USD. I don't know if it's still actually available as there are newer SDR stuff made since. But these things have been available for Wi-Fi field engineers and techs for a long time.
8:30 How I hate this noise. 😬 PLC. I have this problem for years now and nothing changed. The whole street is like a giant antenna. Very anoying on the 49m radio band. And if anyone has a good idea how to filter a class-D audio amplifier, please let me know. A neighbour has a very noise Pioneer amp. The speaker cables act as antenna. Twisted cable or grounded shielding?🤷
@@HB9BLA Yes, this was the first we did. Two 'clip' ferrites on each end of the cable, nothing. Cable wound around a 10x100 mm ferite core, a tiny bit better. Now I think about shielding the wires or try building additional low pass filters for each output.
Your all videos are very informative and I would like to build a long range directional wifi antenna for my village home. Can you guide me how to do this.
I would buy one they are quite hard to build, and you need equipment for tuning. You get them from various suppliers for different purposes (2.4/5.8GHz, Sector or point-to-point). Google Mikrotik or Ubiquity
I have noise from a solar inverter on a street light during the day. Only 1. I cannot get the power company to understand the problem. Clueless they are.
That is bad luck! Here we could send a message to the authorities and they have to come and do the measurements. Then it hs to be removed if it does not comply the regulations.
A device emitting RF noise is transmitting on someone else's frequency. This video talks largely about the Amateur radio bands, where this RF noise can make it impossible to use the frequencies for communicating because the interference is so loud. It's like if you were talking with someone at a quiet party, and someone cranked a stereo. There are laws governing electronics and RF noise. Besides being rude to the people that are licensed to use the frequency it's illegal to transmit/cause interference on frequencies you're not licensed to, even if it's unintentional. Thus the "product pulled from market" things in the video.
@@SeanWalberg The FCC and FAA got on cable companies case because when they left unterminated ends of cables on their system, it caused interference to aircraft or police frequencies . The cable companies cleaned up their systems quickly after that.
Many years ago I helped a friend find S9+ noise on 6 meters. I used HT to track it down to neighbors home a couple blocks away. They were very nice and let us in their house and it turned out to be the power supply on an electric blanket. The neighbors unplugged it and noise was gone and when I looked it up that device had a recall for possible fire hazard so the home owners were happy we talked with them. The next day another S9 noise came and we tracked that to a friends shop when it was closed on weekend. Turned out it was caused by cordless phone base that had built in answering machine. It only made the noise if someone left a message in it . Our friend was also a ham and he said that the answering machine part of that got turned on that weekend by accident and he normally never used it.
Thank you for sharing your story!
A friend of mine had to rewire his whole solar roof (warranty, but a öotnof work) and replace electronics on it, because the neighbouring amateur radio station detected interférence from it.
Before they detected even interferences from the train (BLS).
Both of them had to fix it, as BAKOM told them so.
Euroloop (used by train companies) is well known to create interferences if not installed correctly.
I did a similar exercise at two similar tower block homes in UK and in Germany. The noise levels in UK were 30 dB higher than in Germany leading me to believe that there may be different regulations about sources of noise in the two countries. In UK I have a chinese LiFePO4 battery charger which totally wipes out all HF bands. It is by far the worst polluter. Also in the block I imagine someone is still using a CRT TV as the harmonics seem to change with scene changes in a video signal !
I bought a LiFePo charger for our remote station as a backup for solar. It is a huge polluter, too. Unfortunately, you do not see it before you buy :-(
great video. as a swede, i can tell that each solar installation needs to approve CE, therefore, as a owner of example multiple inverters, sush as microinverters, the CE stamps needs to be revalid as the hole installation is complete. (the install of microinverters does not say the CE stands for multiple installed microinverters, only that it will work with multiple. So in other words, the CE only comply with one unit and not the whole solar installation.. ) //73
So you are lucky that somebody looks at RF noise. Here, the final tests only are to check safety.
@@HB9BLA oh man.. that sucks... here they need to comply to CE and with that, EUs EMC directive..so without review the installation, they cant just say "it comply".. // 73
I live in Houston TX USA where interference is almost continuous from 400khz to 30mhz. It is a "white noise" looking signal that seems to come from all directions. The amplitude is huge, on the order of 5 microvolts per meter so any serious short wave or other long distance operation is futile.
Then the only solution is a remote station, I fear. But for sure, you are not alone :-(
What I did: took out all the fuses in my flat and put them back in one after the other. That's how I found the room that was causing the problem. Then took all the plugs out and put them back in again. So I found the external hard drive that was causing the S9 noise.
vy73 de Micha, DD0UL
So you were happy you had it in your home and only one ;-)
Thanks for your video! Can you recommend a cheap/affordable shortwave radio to detect emissions within the home please? The models in your video look to cost around the £200 mark which seems a bit pricey for me, but I am not familiar with how much they should cost and what functionalities are required. Thank you!
can you tell if your neighbor's PLC is of the variety that allows a hacker to see the whole neighborhood on the same phase? (TP-LINK V1
No. I am not interested in decoding the signal. Just to get it shut down 😉
Nice video. My experience is.... cheap (Chinese) often causes troubles. More expensive... even from China makes in many cases the difference. At home I have a (very cheap) gas powered generator. I can assure it, if I turn on over here, you'll probably will detect the interference in your shack ;-) ! Of course, I never use it, I got it for free for testing.
I am not sure if the price can be used as an indicator. I have unexpensive quiet powerbanks and a quite expensive but "loud" LiFePo charger. It seems to be a bit of luck.
And I have buck and boost converters from one supplier that are quiet (the exact same looking one from another supplier was "loud". So I stick with this supplier and it looks OK up till now.
this is why some circuits from 70' or 80' don't work very well in today's "noisy" homes :( It is annoying because it reduces drastically the range of some DIY built devices :(
Indeed, in the old days we did not have to bother as much with these problems.
WiFi smart switches can be a huge contributor to QRM...
I agree. They use quite steep edges in their signals with lots of harmonics and long "antenna wires"
Your video comes at a very good time! My pal and I are trying to discover why his Sonoff S31's running Tasmota keep dropping off his network. These are 2.4Ghz WiFi. I have the same devices on my network and do not have this problem. He is in a completely different urban area, the Highland Park area of St Paul, MN. I live in suburban Burnsville, MN some 25 miles or so from his location. He has other 2.4Ghz devices that are not affected. I am suspecting radio interference as a potential cause. Besides following the general process you describe, do you have any suggestions about finding interference on the 2.4Ghz WiFi band? We have SDR USB dongles. Many thanks!
Common SDR dongle receivers (RTL2832U) cannot sample the 2.4GHz Wifi band. SDR-Play, HackRF etc are more expensive, but can go up to 6GHz. Good luck finding the issue.
The 2.4GHz band is quite used in many locations. So it easily can be that this device has issues with crowded channels and the source is not QRM but other 2.4GHz devices. As mentioned by @squelchstuff, These dongles do not work up to 2.4GHz. But maybe you can chart a rough coverage of the channels using a Smartphone map? ( Google "ESP32 / 8266 WiFi Signal Strength" ) because CZcams does not allow links anymore.
As Andreas says, you might have more luck with some of the survey apps available for mobile and desktop. They'll show which channels are in use in the locality, signal strength etc. It may simply be a case of manually selecting a less congested channelled, as many users leave their APs on the default channel 1. Search wifi mapper or similar. Netstumbler used to be a popular choice, and many are based on that. As an aside, it seems that some ESP based IOT devices can be prone to this behaviour as is often reported. I've noticed some households with smart lights flashing on and off that have obviously lost their pairing, and have defaulted to setup mode while the residents are away. Burglars must be having a field day. Not smart...
There has been a specific 2.4 GHz spectrum analyzer USB dongle for the last 20 years for about $200 USD. I don't know if it's still actually available as there are newer SDR stuff made since. But these things have been available for Wi-Fi field engineers and techs for a long time.
8:30 How I hate this noise. 😬 PLC. I have this problem for years now and nothing changed. The whole street is like a giant antenna. Very anoying on the 49m radio band.
And if anyone has a good idea how to filter a class-D audio amplifier, please let me know. A neighbour has a very noise Pioneer amp. The speaker cables act as antenna. Twisted cable or grounded shielding?🤷
Usually, we start with adding ferrites into the "antennas"
@@HB9BLA Yes, this was the first we did. Two 'clip' ferrites on each end of the cable, nothing. Cable wound around a 10x100 mm ferite core, a tiny bit better.
Now I think about shielding the wires or try building additional low pass filters for each output.
I made Faraday shields my noisy electronics.
Good idea!
Maybe a good topic for another video ;-) @@HB9BLA
DID I saw DTSU666?
Yes, I built a Solar power plant with a Huawei inverter (shown on my main channel)
Your all videos are very informative and I would like to build a long range directional wifi antenna for my village home. Can you guide me how to do this.
I would buy one they are quite hard to build, and you need equipment for tuning. You get them from various suppliers for different purposes (2.4/5.8GHz, Sector or point-to-point). Google Mikrotik or Ubiquity
I have noise from a solar inverter on a street light during the day. Only 1. I cannot get the power company to understand the problem. Clueless they are.
That is bad luck! Here we could send a message to the authorities and they have to come and do the measurements. Then it hs to be removed if it does not comply the regulations.
@@HB9BLA I sent a complaint to the FCC. Nothing was done
@@JayN4GO Not good. Maybe it is easier to react in Switzerland because everything is small...
😁 "promosm"
??
I know a way scalar wave RF. lol
I do not understand :-(
what is the harm of rf noise. why do i care, could you please explain? thnx a lot for great video.
A device emitting RF noise is transmitting on someone else's frequency. This video talks largely about the Amateur radio bands, where this RF noise can make it impossible to use the frequencies for communicating because the interference is so loud. It's like if you were talking with someone at a quiet party, and someone cranked a stereo.
There are laws governing electronics and RF noise. Besides being rude to the people that are licensed to use the frequency it's illegal to transmit/cause interference on frequencies you're not licensed to, even if it's unintentional. Thus the "product pulled from market" things in the video.
@SeanWalberg: Good explanation. Thank you!
@@SeanWalberg The FCC and FAA got on cable companies case because when they left unterminated ends of cables on their system, it caused interference to aircraft or police frequencies . The cable companies cleaned up their systems quickly after that.
In English please !!
??
I don't know what the heck you mean. Are you a troll?